The effect of population densities of Meloidogyne incognita on the yield of cantaloupe and tobacco

The relationship between population densities of Meloidogyne incognita (Kofoid et White) Chitw. and yield of host crops has been studied by a number of investigators to predict yield losses and for better control of the nematode. Hanounik et al. (1975) found a tolerance limit of a susceptible cultivar of tobacco (Nicotiana tabacum L.) to M. incognita of 0.66 eggs/ml of soil, and Barker et al. (1981) stated that tobacco yield was reduced at 1.5 eggs/ml of soil. In southern Italy, root-knot nematode greatly reduces the yield of tobacco (Lamberti, 1979) and cantaloupe (Cucumis melo L.) but information on the effect of population densities of M. incognita on the yield of these crops is lacking. Therefore two experiments were done in microplots at Ginosa Marina (Taranto) in 1982 to study the effect of M. incognita on the yields of tobacco cv. Erzegovina and cantaloupe cv. Gusto.